Process for making a gas from solid fuels and burning the gas in a close coupled combustor to produce clean heat

Abstract

A process is described for gasifying solid fuels at a constant rate with a small regulated amount of primary air followed by combustion of the gas so formed with a larger regulated amount of secondary air to produce a clean hot combustion gas which is used for process heat, space heating or cooking.

What is claimed is:  
     
         1 . A process for providing clean combustion of solid fuels comprising a means of delivering a relatively small quantity of primary air to the bottom of a quantity of solid fuel ignited at the top, said combustion forming a flaming pyrolysis zone producing charcoal and combustibly gas and moving slowly down through the solid fuel convering all of it to gas and charcoal at a constant rate, and a regulated quantity of secondary air then mixing with the gases to produce substantially complete combustion of the gases which produce clean hot combustion gases which are used for process heat, space heating or cooking.  
     
     
         2 . A device based on the process of  claim 1  in which air passes by natural convection up through a fuel mass in which a slaming pyrolysis zone initially ignited at the top, passes down through the fuel mass relasing hot pyrolysis gases which rise by natural convection through the charcoal resulting from the said flaming pyrolysis and mix with regulated secondary air above the fuel mass creating a clean combustion flame which generates hot combustion gases which to produce clean hot combustion gases which are used for process heat, space heating or cooking.  
     
     
         3 . A device based on the process of  claim 1  in which forced air is provided to a plenum chamber which in turn supplies a small regulated quantity of primary air which passes up through the unburned fuel mass, reacting with the downward moving flaming pyrolysis zone which releases gases and makes char at a constant rate which said gases are then mixed with a regulated quantity of secondary air in a combustion chamber to produce clean hot combustion gases which are used for process heat, space heating or cooking.  
     
     
         4 . A device based on the process of  claim 1  in which an electric blower powered by battery or line power supplies regulated primary and secondary air to produce a clean flame and hot combustion gases which are used for process heat, space heating or cooking.